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So theres always discussion of the relative performance of a turbo-back versus a catback system, and the benefits of adding the split front pipe and high flow cat to a cat-back system, but:

Starting with a stock system, is it better value to just throw on the front/dump and cat and leave the stock catback on there, and save money for something else? Or will an aftermarket catback have a discernable advantage over the factory part?

The car is an R32 GTS-T and my reason for wanting to keep the stock catback, apart from cost, is I don't want it to become loud and I don't fancy big shiny cannons. Is the R32 muffler restricitive enough to warrant replacing?

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Hey man

Basically the stock exhaust is too restrictive to flow anything more than what it does, and you wont see many improvements/gains unless you do upgrade the exhaust.

Exhaust is a good starting point due to the fact the easier the engine breathes, the easier it is for it to produce power, sort of like a healthy person.. if you get what I mean lol

Hence the 2 mods people usually do, turbo back exhaust, and pod filter/cold air intake.

Once the exhaust gases can escape quicker the easier the turbo breathes, less strain, more boost which obviously in turns equals more power.

Doesn't always have to be loud, get a muffler put in, and a high flow cat, or a resonator, that should keep the noise level down.

The ideal size, best flowing is a 3" turbo back. You wont have to go any bigger.

No ones says you have to have a canon just because its a Jap car lol.

Just get a stock straight/twin 3" tip out the back, will look pretty standard to the eye.

Hope some of that helps. :)

Thanks,

Abu

Edited by abu
So theres always discussion of the relative performance of a turbo-back versus a catback system, and the benefits of adding the split front pipe and high flow cat to a cat-back system, but:

Starting with a stock system, is it better value to just throw on the front/dump and cat and leave the stock catback on there, and save money for something else? Or will an aftermarket catback have a discernable advantage over the factory part?

The car is an R32 GTS-T and my reason for wanting to keep the stock catback, apart from cost, is I don't want it to become loud and I don't fancy big shiny cannons. Is the R32 muffler restricitive enough to warrant replacing?

Turbo-back is the only way to go. Putting on a cat back alone is a waste of time.

If you leave the standard front/dump on, the gas comes out of the turbo into a 2 inch tube, then on to a 3 inch tube. The bas is still restricted, so you'll notice little, if any power increase. Ditto if you add just the front pipe and have a standard 2 inch catback.

I went for a Batmbl split front/dump and an HKS hipower silent exhaust. Very quiet, not too large, sounds good on an R32.

At the end of the day though, it's just a pipe. As long as the steel is good quality, and the bends are mandrel bent, any exhaust workshop can make one up for you. I was a bit of a brand whore when I bought that zorst, though I don't regret it.

You can get them through Nengun, though you have to wait a while.

just one questions ... may be related but

anyway

so if you get turbo back exhaust and stay with standard intake or front pipe whatever you guys call it... is that right things to do? i mean as air comes in to engine, say for instance, 20 and with 3inch turbo back exhaust you only flow air out 20 right? but if you get bigger front pipe and say now 40 air can flows in. the 3 inch turbo back exhaust will be able to flow air out 40 maybe..

thats the reason you put bigger exhaust in your car isnt it?

please correct me if im wrong.... not very very expert on mechanic... fu#$kin noob on this area..but this is what im thinking.......-.-;

anyway.....

so! all i want to ask you guys..!!! if you wanna have bigger exhaust, shouldn't you have bigger front pipe to matching the air flow?

or it doesnt really matter just put bigger turbo back exhaust with standard front pipe?

cz just thinking of getting exhaust my self...

thanks....

paul

Edited by tyaos

Thanks abu, that first answer was all I wanted to know :). It's just that some stock exhaust systems aren't restricitive enough to bother with upgrading - in HPI issue 73 they show that a stock GTR catback actually gets more power than an aftermarket bit - and say that since the front pipe and catalytic converter are the most restrictive parts of the exhaust, upgrading after the cat isnt always necessary, as long as the muffler is free flowing.

Kozeyekan - you didnt read the question champ :whistling:

the middle and rear mufflers add a fair bit of restriction. if you ever cut 1 open you will see what i mean. they don't just flow straight through. they do a big S bend through the centre. the rear muffler is less restrictive.

the cat isn't that restrictive, neither is the front/dump pipe. they still add restriction, but not as much as the rear system.

as for mufflers, you don't need a big shiney stainless cannon. ou can just get a 3" oval muffler. they will make the car quieter. companies like lukey and x-force sell 3" oval mufflers pretty cheap, and they work better than a cannon at reducing noise.

just one questions ... may be related but

anyway

so if you get turbo back exhaust and stay with standard intake or front pipe whatever you guys call it... is that right things to do? i mean as air comes in to engine, say for instance, 20 and with 3inch turbo back exhaust you only flow air out 20 right? but if you get bigger front pipe and say now 40 air can flows in. the 3 inch turbo back exhaust will be able to flow air out 40 maybe..

thats the reason you put bigger exhaust in your car isnt it?

please correct me if im wrong.... not very very expert on mechanic... fu#$kin noob on this area..but this is what im thinking.......-.-;

anyway.....

so! all i want to ask you guys..!!! if you wanna have bigger exhaust, shouldn't you have bigger front pipe to matching the air flow?

or it doesnt really matter just put bigger turbo back exhaust with standard front pipe?

cz just thinking of getting exhaust my self...

thanks....

paul

I think you're talking about air coming in, like thru the filter and FMIC etc before it goes in the engine....and comparing that too air coming out the exhasut.

Intake pipe flow = outake zorst flow ???

DEFINATE NO

.....What happens to the air inside the engine...it explodes !

So the volume it takes up is heaps more on the way out.

Part of the reason why turbos actually work,.

If the out was the same as the in, the turbo wouldn't spool enough to FORCE the air thru the intake.

Make sense? :(

PS, the 'Front Pipe' is the pipe coming off the turbo, or the dump pipe. I always get those 2 mixed up.

Most common you might recognise is the front/dump pipe which is a single 'S' shaped pipe doing the job of 2 pipes

I think you're talking about air coming in, like thru the filter and FMIC etc before it goes in the engine....and comparing that too air coming out the exhasut.

Intake pipe flow = outake zorst flow ???

DEFINATE NO

.....What happens to the air inside the engine...it explodes !

So the volume it takes up is heaps more on the way out.

Part of the reason why turbos actually work,.

If the out was the same as the in, the turbo wouldn't spool enough to FORCE the air thru the intake.

Make sense? >_<

PS, the 'Front Pipe' is the pipe coming off the turbo, or the dump pipe. I always get those 2 mixed up.

Most common you might recognise is the front/dump pipe which is a single 'S' shaped pipe doing the job of 2 pipes

thx man

its all make sense!

thx for your info!!!

cheers

paul

Thanks abu, that first answer was all I wanted to know >_<. It's just that some stock exhaust systems aren't restricitive enough to bother with upgrading - in HPI issue 73 they show that a stock GTR catback actually gets more power than an aftermarket bit - and say that since the front pipe and catalytic converter are the most restrictive parts of the exhaust, upgrading after the cat isnt always necessary, as long as the muffler is free flowing.

Kozeyekan - you didnt read the question champ >_<

Not a problem man, glad I could help.

Thanks,

Abu

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